1. Field of the Invention
This invention relates to the field of remote control of objects.
2. Description of the Related Art
The invention of the computer mouse facilitates the control of computer programs via a two-dimensional (2D) graphical user interface. However, because a regular computer mouse is a 2D input device, people did not consider it for physical object control for a long time. To facilitate users' interactions with physical objects, researchers used video to map the real world to 2D space for mouse control. Since that technology requires fixed cameras in the controlled environment for user-environment interaction, people have to wait for property owners to set up the hardware and software before they can try that technology. Moreover, because of the regular mouse usage in that technology, people normally have to interact with an environment using desktops, laptops, or PDAs with pen inputs. The regular mouse based system is convenient for interacting with a remote location. However, it is not very natural for interacting with onsite physical objects.
Since physical objects exist in 3D space, it is reasonable to consider a 6 Degree of Freedom (DOF) input device for physical object control. Many 6 DOF input devices were proposed for three dimensional (3D) interfaces. However, there is still not an obvious winner suitable for all applications. For physical object control, people normally cannot see a cursor float in air without a specifically designed projection system, making it difficult to use most 6 DOF input devices.
To interact with objects in physical world, a user has to locate the object he/she wants to manipulate, and/or specify the path for manipulation. In a virtual world where any object can be moved anywhere, a 6 DOF device is necessary for full control of an object. In the physical world, device movement and data transfer are much more constrained than that in a virtual world. These constraints offer opportunities for controlling physical devices through video of a physical world scene using a regular computer mouse. They also enable us to control devices with pointing device, such as an IR based remote control or a laser pointer. The most popular remote controls are IR based or RF based. Since a regular RF controller is not directional, it normally needs complicated control interface for managing multiple devices. A directional IR controller can reduce user interface complications by using the physical object distribution cue. However, the requirement for the transmitter and receiver pair still limits the IR control system deployment. Similar problems exist for a laser pointer based control system.